


mind meld side-effects may include:

by Werepirechick



Category: Rise of the Teenage Mutant Ninja Turtles (Cartoon 2018), Teenage Mutant Ninja Turtles - All Media Types
Genre: Anxiety Attacks, Canon Compliant, Canon-Typical Violence, Character Study, Dissociative Identity Disorder, Family Shenanigans, Gen, Headspace Weirdness, Hearing Voices, Neurodiversity, One Shot, Post-Traumatic Stress Disorder - PTSD, Protective Siblings, Sibling Banter, area boy concerned about life-threatening events and own mental stability, finally some good fucking content, for once i'm looking at the hints and implications in canon and nodding along, it's been months and i'm STILL reeling from the finale/primiere, its soft boy time, post s1 finale/s2 premiere, thankfully area boy's family is here to give him hugs, wish this fic had more rise gorls in it but alas
Language: English
Status: Completed
Published: 2020-07-27
Updated: 2020-07-27
Packaged: 2021-03-06 02:42:05
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 7,696
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25546105
Author URL: https://archiveofourown.org/users/Werepirechick/pseuds/Werepirechick
Summary: As he prepares to slash a portal to the next building, Leo feels a wave of awareness shiver over his shell. He whirls, odachi raised, heartrate spiking as he searches for the cause. The roof is empty, he can’t spot anyone on the surrounding ones either. And yet the awareness only grows stronger, brushing his tuned senses.“Hello?” Leo asks, then winces at the slight voice crack. Nothing replies, just the sound of New York traffic and normal city life.--Or--Leo starts hearing voices.
Relationships: April O'Neil/Sunita (TMNT), Donatello & Leonardo & Michelangelo & April O'Neil & Raphael (TMNT), Leonardo & Raphael (TMNT), briefly but they're lesbeans harold!
Comments: 26
Kudos: 239





	mind meld side-effects may include:

**Author's Note:**

> DISCLAIMER NOTE: i am not someone with DID, i am someone with ASD. while i can easily empathize with individuals who do have it, i will not try to say in any capacity that i wholly understand their experiences. my knowledge of DID is a combination of having dated an individual who had it, reading/rereading wikipedia articles, and passed around information by irl accounts/experiences online. and let me just wave my hand over the whole premise of this fic and clarify it has a healthy dose of fantastical elements (theyre cartoon turtles, duh), and barring offensive misrepresentation of DID i'd ask people to keep its ninja magic context in mind.
> 
> AUTHOR'S ACTUAL NOTE: me and my friend taytei have been discussing DID raph headcanons for months on discord and the raph & leo centric episodes for "tales of the hidden city" really reinforced those headcanons. (also the hypno episode giving us yet more man vs self symbolism with raph, but i digress.)
> 
> so!!! since i have a big interest in neurodivergent hcs for my favorite characters (you could even say i have a SPECIAL interest, haha) it's fitting that the first new rottmnt fic i publish in ages is about this topic.

They’re all understandably jumpy, the first little while after kicking Shredder’s shiny metal ass. New York itself is jumpy; the rampage of destruction over the course of 48 hours left long, random patterns of ruins. The news hasn’t stopped raving about it, with the internet being even worse- but, hey, if someone wasn’t in the know about what went down, the fearful confusion is natural.

Leo _is_ someone who knows the details, however, which is why he feels irked that an unease hasn’t left him even a week later. His injuries, like the rest of his family’s, have healed enough that he can be reasonably trusted not to keel over in a gutter. The immediate two days following Shredder’s banishment were spent basically living in each other’s pockets; no one had been eager to be alone overly long.

Raph is still feeling like that, even if he won’t admit it outright. His fretful clinginess is part of why Leo is roaming on his own right now; like, of course he loves his big brother, but Raph’s anxiety about abandonment has ratcheted up to an overwhelming level. He just needs some space and a bit of fresh air, then he can head home and let Raph smother him with affection again.

Leo wishes Mikey the best of luck, since their youngest brother is an even bigger target for mother-henning, and Leo and Donnie have both scampered off for alone time tonight.

Alone time which, admittedly, isn’t helping as much as he’d hoped. Leo stops off on a building overlooking a torn-up street; it used to be a string of shops, cafes, and the like, but now it looks like a tornado blew through. The sight of the damage makes him feel a little queasy, silent judgement of his own actions coming to mind not for the first time.

Maybe if he’d been faster, maybe if he’d been cleverer. Maybe if he’d talked Big Mom into a better deal, maybe if he hadn’t squandered so much time making sure everything lined up _just so_. Then maybe this street and dozens of others wouldn’t be in the state they are.

Three days. Three days of nonstop fighting, that’s what his siblings had to face. All while Leo was playing strategy games with Big Mom, hands and mind practically buzzing at the challenge to outwit her.

He’d had _fun_ , doing that. And that’s probably the worst part about his guilt; knowing that while the rest of the world was on fire, living in constant terror, he was fully utilizing his skills for the first time ever and finding it _exhilarating._

Leo rubs his eyes, tired deep inside where even extra hours of sleep can’t reach. How depressing; his nighttime stroll is turning into a pity party. He sighs to himself, turning away from the unpleasant view.

As he prepares to slash a portal to the next building, Leo feels a wave of _awareness_ shiver over his shell. He whirls, odachi raised, heartrate spiking as he searches for the cause. The roof is empty, he can’t spot anyone on the surrounding ones either. And yet the awareness only grows stronger, brushing his tuned senses.

“Hello?” Leo asks, then winces at the slight voice crack. Nothing replies, just the sound of New York traffic and normal city life. A sliver of fear is creeping into his heart. The unnerved state he’s been in all week heightens.

Leo’s breathing is controlled, but if he lacked even a quarter of the training he’d been given, it would’ve come out as quickfire panting. He feels it, he _feels_ something with its eye on him, it’s close and he can’t see it. It feels- predatory, strong, _big._

Leo feels cornered on the exposed rooftop, and the heavy, stalking presence is suddenly _right behind him._

Enchanted metal whistles through the air he swings so fast. Leo’s arms jerk as the momentum carries, nothing to stop it as his blade slices thin air. He stumbles, recovers, casts a terrified glance around himself.

There’s nothing there, the rooftop is still empty.

Leo’s entire body locks up as the presence comes up from behind him a second time. He doesn’t move a muscle, tight gasps of air all that he’ll allow himself. The- the _thing,_ whatever it is, looms over him, he can feel how much bigger it is. A phantom weight is settling on his shoulders, his shell; a low, quiet rumble coming from a throat just above his head.

And then it’s gone.

Leo rips open a portal and tumbles into his home, shaking as he closes it so fast it nearly clips his foot. He’s crouched on the floor for a moment longer, searching for a sign that the _Thing_ followed him or not. When nothing else happens, he runs out of the atrium.

Mikey and Raph are playing a movie in the living room, the projector screen showing the aged footage of one of their dad’s lesser known films. Leo trips on his own feet as he yanks off his gear and drops his odachi, ignoring the confused greetings he receives as he launches himself into the pillow pile that’s been constructed. He steals Mikey’s blanket, wrapping himself in it and shoving himself up against Raph’s side.

“Leo, what the heck?” Mikey questions grumpily, tugging at the edge of the blanket. Leo shrugs him off and curls up tighter.

“Dude, you okay?” Raph asks in a gentler tone, putting a careful hand on Leo’s shell. Leo has his head under the blanket and pushed into a pillow, he can’t see anything but darkness, and can’t feel anything but his brothers and the soft fabric. He takes a shuddering, wavering breath.

He hears Mikey’s indignant tone shift to something else, hears his brothers whispering back and forth. The hand on his shell starts rubbing slow circles, smooth and grounding. Leo’s eyes are dry as he stares into the dark, focusing on breathing, not protesting at all when Raph carefully lifts him into a better position. Leo feels another, smaller body add itself to the hug, wiry arms cinching around his middle as Raph loosely holds them both.

The weight and presence of his brothers quiets the sheer panic. Leo is grateful to feel the attack subsiding bit by bit, mind clearing. When he raises his head, blanket falling back from his face, he finds himself still the center of a hug-sandwich. The movie is playing at a lower volume, subtitles on the screen so no dialogue is missed.

“You good, Leon?” Raph asks, noticing Leo’s emergence from hiding. His expression is warm, concerned, but has a shadow of grimness. _They’re all a little jumpy._ “Something happen?”

“I…” Leo shakes his head. Looking back, he comes to the swift conclusion he let his paranoia get to him. “It was dumb. I scared myself into an anxiety attack. There wasn’t anyone there.”

“Anyone where?” Mikey tilts his head, shifting his position to be a bit more away from the cuddling.

Leo grimaces. “Just some roof. I was, uh… I was out for a walk, thought about stuff longer than I should have. It, uhh… yeah, it was nothing. I scared myself, that’s all.”

“That’s rough, buddy,” Raph says soothingly, squeezing Leo in a side hug.

Leo nods, feeling embarrassed now. “Can we watch Avatar after this?” he asks at the quote, knowing the film will be over in a few more minutes.

Mikey makes an interested noise. “Sure, what book? I’m voting for after Toph joins up.”

“Duh. She’s the best character.”

“Raph seconds that. Intro episode?”

“Totally. Text Dee n’ see if he wants in on this.”

Leo settles deeper into the pillows, putting his bizarre, self-inflicted experience out of mind. Raph shoots off a text to their absent sibling while Mikey turns back up the volume, their shared space now more spread out with the crisis resolved. Leo zones out comfortably until Donnie arrives, his birthday twin inserting himself into the arrangement, and then, with drooping eyes, Leo relaxes properly. He’s asleep soon after Toph finishes throwing grown men out of a fighting ring.

-/-

“Y’know, I can’t say I’m surprised all that much,” Raph says, turning in a slow circle as he looks around.

“What can I say?” Leo preens, flipping his mask tails over his shoulder. “I know awesomeness when I see it, and that’s _me, baby.”_

“Sure,” Raph snorts, but the derision is fond. Leo still huffs dramatically and waltzes away, admiring his grandiose space. The high vaulted ceilings, the elegant, renaissance-style portraits of himself and the people he cares about flowing along it. The fountains gushing water sparkling with diamonds- safe for drinking despite that. Heroic, golden statues of himself on pedestals line the hall, some adorned with the extra decoration of resting butterflies or carelessly tossed accessories- boas, necklaces, hats, other finery.

Leo breathes in, reveling in the sunlight pouring in from an impossible light source, given they’re underground. The waterways carved into the floor are filled with swimming birds and jaunty smiling flowers, which he stoops to pick one of. Twirling it between his fingers, grinning as the flower sings a warbling song about his amazingness, Leo misses just how far Raph has wandered off. It’s the creak of neglected hinges that makes him drop the flower and spin around, spotting his brother peeking into a doorway in the wall. He’s abruptly standing inside the cavernous room within, feeling almost like he’s been swallowed by the long rows of shelves, slick oil paintings, and leather-bound memoirs.

“Hey! A little privacy!” Leo yelps, darting out of the dark room and slamming the door shut behind him. “That’s not for you or anyone else to see!”

“Sorry! I didn’t know where that went,” Raph says, hands raised. “You don’t have anything labeled at all, how was I supposed to know that was your-”

“Don’t talk about it either!” Leo barks, shoving the room full of insecurities and mistakes and general Awful Stupid Shit He Regrets Doing from his mind. The door disappears behind him, seams melding into the crisp blue wall. Unfortunately, it just spawns again a few meters down the hall. He glares at it, offended but not surprised.

“You should probably actually, I dunno… try to deal with that stuff? Instead of repressing it?” Raph says awkwardly, scratching his flat nose. “Ah… Not that we have much leg to stand on.”

Leo gives him a questioning look. Raph shrugs. “There’s only recent stuff that’s started to overlap. A big chunk of it is still all separated- _somebody_ is kinda territorial about what’s ‘his’, the jerk.”

“Why’s that?” Leo asks.

“Trauma does that sometimes? I don’t know. Ask him yourself next time you see him. And actually label stuff in here, _jeez._ What if you’d let me walk into a room with, like, _seriously_ private stuff?”

“What?” Leo says, blinking at his bedroom ceiling as he wakes up. He’s still woozy, confused by the certainty he was somewhere else just a second ago.

-/-

“Why do you even keep trying, man?” Leo drawls, weaving between the tentacles snapping in whipcracks at him. “No one wants your gross food, get a new hobby!”

“ _Insolent peon,”_ Meat Sweats spits, withdrawing his eldritch nightmare of an arm for a reprieve. “What do you know of _fine cuisine?_ I’d wager good money that you live on microwavable comfort foods and greasy takeout!”

“I mean, yeah, but you don’t have’ta call me out like that-”

Meat Sweats bellows and lashes out again, drowning out the rest of the fight around them for a solid moment. Leo is a touch too slow to duck in time, but the kick sweeping his legs out from under him saves his shell. April grunts as she half-catches him while Leo recovers, and then stands up to brandish her bat.

“You tried to hypnotize my- Sunita, into eating your overpriced hipster crap!” April shouts, stuttering only a little on her friend’s name before recovering her righteous spirit. “I got a bone to pick with you for that, you ugly Peppa Pig ripoff!”

“You take that back!” Meat Sweats exclaims indignantly.

“Make me!”

“So, you got this? Yeah, okay, you got this,” Leo says as April charges in, swinging her weapon and sending Meat Sweats’ tenderizer flying as they connect. He hovers for a moment, calculating if he should flank her or find someone else to engage with- Hypno is off to the side of the restaurant he and Meat Sweats ‘acquired’, giving Raph and Mikey a bit of trouble. Raph’s jutsu isn’t suited for indoor spaces this size, same as Mikey’s kusarifundo and its flames. The sheer-edged ring blades are ricocheting in deadly arcs around Leo’s brothers, slicing thin cuts when one isn’t fast enough to dodge.

Leo wonders where Donnie went for a second, vaguely worried, but he spots a flash of purple through the kitchen door windows. Ear splitting screeches and a blast of odd colored smoke follows as Donnie deals with the monstrosities that have been cooked up.

Yeah, Donnie is fine and April is well on her way to avenging (the currently unconscious) Sunita’s honor. It’s Meat Sweats’ own fault for losing hold of his weapon- now April has a _giant spiked mallet_. She is terrifying and Leo is very glad she’s basically his big sister.

“You should really ask her out after this!” Leo shouts at April before he goes to assist Raph and Mikey.

“Shut up, Leon!” April yelps, flustered.

Leo leaves her to her meat tenderizing and hops through a portal, intending to drop onto Hypno. He pops out where he wanted, falling from the ceiling, but he’s caught by an open palmed strike and sent flying into the wall. Leo wheezes and whines, hand going to his throbbing stomach. Raph stands between him and Hypno, the hippo mutant chortling to himself as he sets Leo’s own brother on him.

“C’mon, Raph,” Leo says in exasperation, “what the heck did Donnie make those earplugs for if you’re just gonna lose ‘em?” He’s prepared for the carefully aimed wire that wraps around his sword hand, yanking Leo to the side as Raph punches a hole through the stone wall.

Leo feels Mikey snap the tight ear-protectors over his head, nodding in thanks to his little brother as he stands back up. No time to dig out his own pair, Raph’s will have to do. Hypno flings another volley of slicing rings, Raph thundering towards them with a vacant stare soon as they’re cleared.

Leo grits his teeth and reluctantly prepares to deal with their older brother. They’ve handled Raph’s rare intense episodes of disassociation before- the wild, territorial second personality he has- but this is different, and it feels dirty, and Leo just hates the idea of having to even try hurting his brother, alright? Still, he raises his odachi to deflect any attacks away from Mikey, make some kind of opening for his little brother to jump in-

**_KICK UP._ **

The abrupt order has him kicking straight upwards, redirecting the haymaker Raph was aiming. Leo is absolutely baffled and therefor frozen in a high-kick stance. Thank god Mikey is there to tag-team the fight and dart through the opening. The shriek of kusarifundo wire going taut jolts Leo out of his stupor, Raph stumbling back as his arm is pulled flush to his plastron by Mikey’s weight.

**_DROP HIM DOWN. PIN HIM._ **

Leo is hearing a booming voice that comes from nowhere, and he’s pretty sure it sounds like his hypnotized big brother. _Exactly_ like him.

But that’s a good idea, so hallucination or not! Fuck it.

“Mikey- _jump off!”_ Leo yells, slashing a precise circle around his brothers. He has a split second to read Mikey’s lips saying _“wait, WHAT?”_ before they both fall through the portal. Leo spins on his heel to see where the other portal opens: right over the totally-not-up-to-code children’s playground, Raph’s broad form crushing the infrastructure and landing him deep in the ball pit.

Mikey, the brilliant gymnast he is, is perched up on the top rungs of the unsafe play zone. Leo sighs in relief that he jumped clear just in time. Mikey is gesturing animatedly and probably shouting at him from across the restaurant, regardless of Leo’s inability to hear.

 ** _GO LOW_** , orders the voice and Leo obeys without hesitation, only a glint in the corner of his vision to tip him off. A slash of steel goes over his head as he rolls out of the way, Hypno’s expression furious as he attacks repeatedly. Leo just keeps clear for another few moments, hopping back and back and back from Hypno’s range- and then the flying rings are tossed again and he collects each one neatly in a portal.

Disarmed, Hypno’s face goes from angry to paling. Leo grins.

There’s a low, purring rumble behind-beside-somewhere near Leo, which is kinda sucking the joy out of his trick. He feels a little hysterical, actually.

“You wouldn’t happen to be hearing a giant cat that sounds kinda like my brother, would you?” Leo asks in a strangled voice. Hypno gives him a _look._ “Ah, yeah, I didn’t think so.”

Leo laughs, because what else can he do? And then he’s not doing much of anything, what with Meat Sweats’ fist colliding with the side of his skull.

-/-

The heaviness over top of him is… not exactly smothering, but not very comfortable either. Still, the Thing resting on his sternum fails to inspire discontented feelings. If Leo were asked, he’d describe it as a warm sort of resignation? A simple fact of things.

Someone is… talking to him. Hands are fluttering over his body, touching his throat, the back of his head, opening an eyelid and shining a light that dances from there to the next eye. The fingers let his eyelids slide shut again. Leo feels… _ow,_ he feels his sense of pain coming back to him. Leo tries to pull himself up from the blackness of semi-unconsciousness.

 **NO,** says the Thing and presses him back down. **NO MOVING. HURTING, STAY STILL.**

“Leo? You with us, dude?” Donnie asks, beside him but sounding so far away. “I saw you twitch. Squeeze my hand if you can hear me.”

Leo tries to- he can’t really feel his limbs, but he _thinks_ he manages it. The Thing growls and reaffirms its position across his middle. It’ll get worse if he gets up, him wandering around with a head wound without anyone watching out for him- no, staying still is better, wait for him to wake up, then the noisy blue one will be **safe** again.

“’m not that noisy,” Leo protests in a mumble.

 **VERY NOISY,** the Thing grunts.

“Maybe we should call Splinter?” says April, warm hand vaguely present on his opposite side. “He’s not making any sense.”

“Slap him, that always works,” Mikey suggests from further away.

“In _movies,”_ Donnie retorts.

“I’ve done it to him when he won’t wake up for breakfast, it worked then.”

“Don’t slap your brothers awake, Mikey,” April admonishes with a poorly hidden snicker.

Leo doesn’t know what’s happening, feeling like he’s falling while floating, unable to see or really even feel anything beyond an ache to his skull. He thinks loudly that this is all highly annoying and would like to wake up now, thank you.

 **NOT YET!** snaps the Thing, its presence growing to engulf Leo’s thoughts entirely. Leo- he- they need to stay right here, wait for help, keep still and don’t make the injury worse, play dead so no one takes any interest.

_“You- jeez! You know we can’t be here! This is really rude even for you.”_

The Thing is suddenly and forcibly yanked away, snarling as it’s taken. Leo inhales sharply as his eyes fly open and he regains control of himself. “Oh, thank god,” Donnie says, pulling back the sparking end of his tech-bo. “I wasn’t actually sure if that would work or not.”

“Donnie!” April scolds.

“So Donnie can pull electro-therapy nonsense, but I can’t slap him?” Mikey gripes, crossing his arms. “Unfair, dude. Seriously.”

“Why is everyone trying to beat me up?” Leo asks weakly, wincing as his hand meets a tender spot on his head. The whole right side of his face _aches._

“They don’t mean it, you know that,” Raph says with a fond tone. “They were just worried.” Leo mumbles a reluctant, irritated agreement.

“You got knocked out, we might’a been panicking a tiny bit,” April admits sheepishly. Her arm slides under his back and carefully helps him upright, holding Leo as things swirl in his vision. “Donnie said your pupils were equal still, and there’s not as much blood as there could have been… So how’re you feeling?”

“Like I got knocked out by a nine-hundred-pound swine.”

“Closer to a thousand now, actually,” Donnie says as he shuffles closer on his knees. He has his goggles down, tapping on his wrist interface without glancing at it. Leo blinks woozily and doesn’t question the ogling. A few beats later, Donnie nods and sits back again. “Alright, I don’t have the scans I could do at home, but I don’t think you’re in any danger of spontaneously expiring.”

“Good,” Mikey says with a low, firm voice. Leo looks past April and Donnie, spotting their youngest sibling playing guard for the two trussed up, beat up mutant assholes that did this to him. Mikey has his Dr. Delicate Touch expression on, which is a warning in itself about his mood.

“If he really did get hurt,” Mikey tells Hypno and Meat Sweats, “then I was gonna make tonight’s special marinated pork strips and flambe’d hippo steaks.” His kusarifundo has its demonic jack-o-lantern spirit activated, the burning ball of blades grinning, cackling at the adult mutants threateningly.

“Sorry, mate,” Meat Sweats whimpers, shrinking away from the flames. “I was just trying to help me business partner out, see? Swear it wasn’t s’pposed to be more than a love tap-”

The ‘fundo’s blades shriek against the tile floor. Meat Sweats shuts his mouth.

“Dad said no vigilante justice, Michael,” Donnie reminds dryly. “He’s- aaaand he’s not listening. April, could you wrangle him? Yeah, thank you. Leo, you sit here and don’t pass out again; I’m gonna check on Raph.”

“Whuh? But he’s right h… ere.” Leo’s words die in his mouth as he looks around, finding no sign of Raph at all.

Donnie narrows his eyes at him. “I’m gonna check on Raph _quickly,”_ he amends, and then is up and gone.

“But, he… I swear he was,” Leo says to himself, trying to make sense of what the hell is happening. His temples throb as his headache asserts itself, making him squint and wince every time April and Mikey get above a certain decibel. Sunita soon stands up shakily from the corner they laid her in, diffusing the short argument over how ‘separated/alienated from society’ someone has to be for it to not count as vigilantism. Leo thanks the universe’s small mercies for it.

His gratefulness, however, is dispelled by Raph reappearing with Donnie.

-/-

The next night comes and Leo marches into his birthday twin’s lab without invitation or permission. Mikey is sitting on a table being scanned by something while Donnie takes notes. Leo doesn’t hesitate to fling himself at twin and cling to him around the neck.

“Donnie,” Leo wails to him, “I’ve officially gone _crazy.”_

“Oh no,” Donnie deadpans, not even blinking while Leo slowly slides to the floor. He takes a step back and lets Leo flop facedown. So cruel! Leo is still recovering from a head injury, a wide bandage taped over it and everything.

Heedless of that, “You gotta help me,” Leo begs, reaching a hand to clutch Donnie’s ankle. The merciless bastard steps back out of range without comment.

“I don’t ‘have to’, actually.” Leo makes a high pitch whine. Donnie sighs loudly, rolling his eyes so hard Leo can hear it in his voice. “But I _could_ be persuaded… I guess.”

“Anything, I’ll do anything!”

“Dangerous words to say to me, Leonard, but so be it.”

“Y’all’s personalities are two-thirds pure dramatics,” Mikey says.

Leo lifts himself up off the floor, rising to give Mikey an annoyed stare. Their youngest sibling ignores him, rolling a sucker between his teeth as he jabs away at his Switch.

“Why are you here again?” Leo asks.

“Because when two dads _really_ hate each other-”

“He grew an inch these past three months and I’m updating his x-ray scans,” Donnie answers.

“Ah.” Leo glances at the game Mikey is playing. He opens his mouth and then closes it, brow furrowing. “What’re you doing to your villagers?”

“Trapping them in isolated holes against the sea. Why?”

“I…” Leo decides it’s not worth pursuing that conversation. He turns back to Donnie. “Right, okay, uhhh… I think I’m losing my mind and I’d like some clarification on this.”

Donnie raises one precisely crafted eyebrow. “Describe the symptoms and/or whatever weird thing you ingested in the last 24 hours.”

“I didn’t eat anything weirder than usual, and it, um, started a few days back, I was out on my own ‘cause I needed some air, and…”

Donnie nods along, a list forming on his iPad. By the time Leo reaches the end of his experiences, Donnie seems like he’s come to a conclusion.

“Well?” Leo presses, desperation creeping into his voice.

“ _Well,”_ Donnie says, “there’s a lot of different things that could be causing this. Sleep deprivation, triggered flashbacks, hallucinations brought on by stress and trauma- oh, and our family does have a history of mental disorders and illnesses, so.” He shrugs. “I’m not a real doctor though, at least not in general medical fields, never mind psychiatry. Best talk to dad?”

Leo groans and puts his face in his hands. He wants to avoid that, honestly, because bringing it up with Splinter would make it all very _real_ and possibly serious. He doesn’t want to be crazy, there’s enough going on in his life it’s the _last thing_ he needs.

“Chill, dude,” Mikey says when Leo mutters something along those lines. He actually pauses his game and turns off the screen, giving his full attention. “It wouldn’t be a world ending deal, right? Raph’s pretty much for sure got DID and all that, and he’s living his life just fine. We’d still love you and treat you the same way as we ever have.”

Donnie adds onto that. “I was going to save it for later, but on a related note I can’t help but notice the ableist terms you’re using to describe the situation.”

“Not now, Dee,” Leo says miserably.

“I’m just saying. You wouldn’t call Raph crazy or insane, would you?”

“…No. ‘course not. It’s just-”

“Then you should extend the same respect to yourself as well. Being scared of uncertainties is normal, but you know better than to demean yourself for things you can’t control. You’re still yourself regardless how this pans out, and you’ll have your support network to help you through it, every step of the way.”

Leo lowers his hands, meeting Donnie’s gaze. He huffs soft laughter a beat later. “You’re reading off a script again, aren’t you?”

“Riffing off one,” Donnie corrects, closing the article on his iPad and setting it aside. “But the intended message of things is the same, whether I use someone else’s words or not.”

“Wow. I think your emotional literacy has deepened to a whole tablespoon’s worth now.”

“Thank you, I’ve been working hard. Next step is perfecting how to ‘ _hug’_ a person.” Donnie makes quotation gestures as he says that. Leo snorts and feels a little better. Donnie then contradicts himself by giving Leo a perfectly acceptable hug.

“I needed that, thanks,” Leo says as they move apart. He notices Mikey staring intently at him. “What? You want one too?”

“I wouldn’t say no to a hug, but that’s not it,” Mikey says, hand under his chin as he visibly thinks hard about something. “So like, no judgement on you making co-pilot alters of our brother if you really did, but those sound pretty much exactly like Raph’s? _Exactly_ like his?”

“Yeah, and?”

“And weren’t you two the only one’s to figure out the mind meld trick?”

Leo stares, processing. Donnie’s palm smacks against his forehead.

“Oh my god,” Leo says as it dawns on him. “I’m an idiot.”

“Only sorta,” Mikey teases. “Raph, too, since he apparently hasn’t noticed you’ve been sharing headspace this entire time.”

“No, it makes some sense,” Donnie interjects, flapping a hand as he rapidly texts someone with the other. “Leo would have to consciously use the connection for it to work, but Raph- Raph has two other people in his head.”

“He doesn’t notice because it’s not _him_ that’s reaching out to me,” Leo groans, facepalming.

“ETA less than a minute,” Donnie says, tucking away his phone. “I think we’ll get this sorted out now pretty quick, lucky for you.”

“What ETA?” Leo asks.

“Of-”

Raph skids into the lab, somersaulting as he trips, careening towards them. Leo and Donnie spring upwards and grab the ceiling to avoid being run over. Mikey manages to balance on his table regardless of the jarring impact of Raph’s crash landing, resuming the torture of his digital villagers.

Raph is up immediately and shouts, “LEO I’M SORRY I DIDN’T KNOW I WAS DOING THAT,” and bursts into overwhelmed tears.

“Donnie, no,” Leo says in disapproval. “Where’d those nice gentle words go?”

Donnie shows no remorse for whatever terribly phrased message he sent. “I used up all my socializing juice for the weekend, try again later.”

“DID THE SAVAGE RAPH FIND YOU? OH GOD HE DID. MIND RAPH IS SO MUCH NICER I WISH YOU’D MET HIM INSTEAD-”

“A proper explanation would be nice, Purple,” says their dad from the doorway, sounding already tired of the conversation. “Why is Red crying?”

“Donnie’s fault,” Leo tattles as he drops down. He’s already prepared for the bearhug he’s nabbed in by Raph, patting his brother’s back and trying to help him calm down.

“Snitch!” Donnie accuses.

“I was witness, he did a bad,” Mikey says lightly.

“ _Snitches!”_

“Donatello, come off of the ceiling,” Splinter says, pinching the bridge between his eyes. _“I should not have to say that to my children, honestly…_ The four of you, we will discuss this in the kitchen over tea and cookies. This will likely take long enough you will need extra glucose.”

“Sure thing, pops,” Leo says amiably. He pats Raph’s shell a little more firmly. “C’mon, big guy. Either put me down or carry me there, I don’t care which, but I want those cookies.”

Raph sniffle-snorts disgustingly and starts walking. Leo resigns himself to the escort downstairs, smiling ever so slightly as he shushes his brother’s many apologies.

-/-

With the sheer amount of craziness happening when their dad taught them the advanced Hamato clan techniques, Leo can’t say he’s surprised something got missed. There’s probably something to be said there about them not leaving important stuff until the last second before a deadline, but then again…

If it all works out fine, then why worry about it?

“Not the best attitude to have about uncontrolled psychic links,” Donnie comments, “but live your best life, I guess.”

“You’re just jealous you can’t do it _too~”_ Leo teases smugly. Donnie looks him in the eye and then taps a button.

Leo jolts and yelps, reacting to the harmless but startling shock from the wires taped to his head. He glares at his brother, who is smirking. “What _is_ it with you and shocking me?” Leo grouses.

“You make funny sounds,” Donnie says in monotone, even if his eyes are full of mischief.

“I could walk outta here, y’know,” Leo mutters, but makes no move to get off the table. Donnie doesn’t bother to reply, which means he knows Leo has no intention of leaving yet. Leo scowls and swears to get payback- maybe shifting everything in his twin’s room/lab just an inch to the left? Shelldon could be bribed with a polishing session, which would mean there’d be no video evidence of Leo sneaking in while Donnie is asleep…

“Alright, he’s in REM-sleep,” Donnie announces, glancing at one of his monitors along the wall; a graph for heartbeat, breathing rate, blood pressure, and brain activity is displayed alongside a goofy picture of Raph smiling toothily. Donnie checks the setup one last time, saying to Leo, “We’ll start with twenty minutes, see what happens. I’ll pull you out at that time and you can take a break; I wanna see if Raph has any physical reactions afterwards.”

“Cool,” Leo agrees, settling himself into an easy lotus position. He breathes in, breathes out, closes his eyes and finds the center of himself. With no further fuss, he slips into meditation and follows the intangible connection which leads away from himself.

It’s ‘late’, by their family’s standards, with the early morning beginning aboveground. Leo is just going to sleep a little longer in the afternoon than usual, same as Donnie; it’s worth it to conduct this experiment, which can’t happen unless Raph is asleep. There’s a moment where Leo gets snagged by that feeling of warm slumber, but he tugs free easily enough, even if part of him is tempted to settle down for a nice nap. Pulling together a mental visual of himself comes next, just before the tranquil void unfolds into color.

Being there-but-not-there in Raph’s mind is still a novel experience. Leo’s headspace feels _real_ to him, if in an uncanny valley kind of way; being in someone else’s is less so, letting him see the metaphorical seams to what’s basically a never-ending dream. Not that it diminishes the wonder of it.

There’s a lot of psychological mumbo-jumbo to how it all works, but much as Leo has begun to appreciate a good brain teaser, trying to analyze his brother’s inner most self is rude. The ground rules they laid out specified as much for both of their headspaces; visitors welcome, but only with permission and a promise to look, not touch.

It’s not the same as sharing immediate, conscious thought space- that felt somewhere between plunging underwater and balancing the ends of a seesaw. Enveloping them completely, while requiring concentration to maintain equal presence in their thought process. With one member of the connection unconscious, it’s closer to visiting a carnival funhouse. He’s _in_ Raph’s mindscape right now, but they’re not meshing together.

Which means rather than seeing the world through dual perceptions, Leo gets to stroll through the uneven, chaotic constructs that form his big brother’s headspace. There are three distinct areas that he can reach like this, though in the ‘distance’ he can spot fuzzy shapes that might be others. Not important; it’s the fully formed personalities that Leo is supposed to possibly interact with.

The largest area is the ‘closest’- space is relative to perception, in here, it’s _weird-_ and it belongs to the Raph they see the most often. Each section is somewhat walled off, but there are gaps and breaks in those walls, so parts bleed over in places. Still, it’s easy enough to tell them apart. The most prominent Raph personality has an _endless_ number of framed photographs, tacked up floor to ceiling on the brick walls. Every photo is of their family and friends, seemingly random memories displayed with wholehearted adoration. Leo doesn’t linger near the openings into the area, but the pictures make him smile. They, along with the way portions of the stone floor melts into gym mats or comfy blanket piles, are just so very _Raph_ in the best way.

The area he’s been directed to investigate tonight- non-invasively! A cursory pass, nothing more- is the furthest from where Leo entered, sequestered in partial shadows. (The architecture of things doesn’t make sense, makes even _less_ sense if pondered on, so he lets it be.)

The tidy, well-maintained concrete floor of their home becomes rougher under his feet, shifting into worn sewer tunnel and natural rock formation. The walls are thicker, covered in roots and murky lichen. Some have faint graffiti that possibly depict familiar faces, but most are too faded to make out. Water splashes against Leo’s ankles as he ventures past those walls, mud swirling in the crystal-clear shallows with each step. The area is dark, oppressive almost, but it smells like rain and feels like nostalgia, bringing flashes of _seriously old_ memory.

Leo almost misses a door in his wandering, backtracking a step when he notices. It’s a metal maintenance entrance, beat up and rusting; there’s dozens in the underground his family inhabits. Leo whistles merrily as he grasps the door handle, heedless of the deep gouges in the metal and surrounding stone walls.

A heavy weight slams it shut abruptly, before the door is even an inch open. Leo laughs and drops his hand, stepping away from the clearly marked door with its sign stating: DANGER – DO NOT ENTER. Personally, Leo thinks the warning stickers indicating ‘large animal attacks’, ‘explosive materials’, and ‘health hazard’ is a bit overdramatic, but that’s just his personal opinion.

“Yo, big guy,” Leo greets cheerfully, craning his neck to look upwards at the looming figure. “I swear I wasn’t _actually_ gonna go in, I just needed your attention. See, Don sent me, ‘cause he and Raph were hashing out some experiment plot and I’m the only one who can- _oh,_ uh, okay um-”

Leo is disappointed but not surprised, finding himself picked up and carried back the way he came. _Savage_ , as Raph named him, has him firmly under his arm and is wasting no time carting Leo back out of his territory. Leo blows out a harsh breath and says, “You could at least hear me out about everything, okay? Sorry I couldn’t exactly call ahead, your land- _vine_ wasn’t working.”

Savage doesn’t laugh at the joke. Typical tough crowd.

“You’re no fun,” Leo says, crossing his arms.

 **“…Noisy,”** Savage growls in a low voice, and- do his eyes deceive him!- mouth curling upwards at the corner.

“I am not!” Leo protests in mock offense, and proceeds to talk Savage’s ear off the whole way. Of the three personalities, this one is the least socialized, far as they’ve theorized. Something that Raph has been wanting to work at is changing the unpredictable, volatile reactions of Savage; it’s not that the personality is a _bad_ person… he just doesn’t have the same experience building blocks the other two do.

Quickest way to amend this? Easy. Just aggressively befriend Savage until he can tell his family from foe, just as naturally as the other two do. Hence why Leo is chatting with Savage despite the lacking responses; regardless of past misunderstandings and mistakes, Leo firmly loves all aspects to his big brother. He’s willing and happy to assist in desensitizing the semi-feral personality to the broader world’s chaos and noise.

But before he knows it, they’ve made it to the next area over and the double doors of it are kicked inwards. Leo hardly has time to brace himself before he’s lobbed through the air like an underhand pitch.

“Be careful!” scolds a clearer voice, catching Leo without looking and setting him down in the same motion. “Look at how tiny he is compared to us- especially to you! Would it kill you to try being a _polite_ host for once?”

Savage pulls back his lip to flash canines, snarling before he stomps off. Mind rubs his temples and sighs long-sufferingly. Leo reaches up and pats his brother comfortingly.

“I would’a landed on my feet, it’s not big deal,” Leo assures the fretful personality.

“That’s not the _point,”_ Mind says. “We’re the big brother, it’s our job- ugh, never mind, he never listens and neither do you.”

“Now hey,” Leo defends mildly. He grins at Mind. “So what’s up? How’ve you two been?”

“Better, actually!” Mind says, excitement in his tone. “Since you guys started interacting more with Savage lately, I’ve finally had time to organize stuff. I didn’t even realize how much of my attention went into keeping him in check until I stopped having to so much, y’know?”

Leo nods. “That’s awesome, dude. Raph’s been having an easier time with, like, a whole bunch of stuff too. Mostly anxiety things. I wouldn’t’ve noticed if I weren’t looking for it probably, but he’s chilled out from all’a the stress fighting Shredder gave ‘im.”

“I know,” Mind says with a fond smile. “I’m neighbor to him, remember? Those two might keep themselves separate for the most part, but I stay involved with both. It’s my job to take care of our family, right?”

“Right. And you do a good job of it, too, even if you hover too much,” Leo says, lightly punching Mind’s bicep. His complaints have no sincerity, which he knows Mind knows, and so he gets shoved away as his brother rolls his eyes. Leo laughs and skips backwards, turning on heel to trot off into the domain.

Savage’s territory is reflective of his solitary, instinct driven nature; Raph’s is as warm as his outpouring affection, blatant in how much he _cares._ Mind’s is neither of those things, even if it borrows elements here and there.

Mind’s area of the shared headspace is smaller than the twisting tunnel maze and the sprawling duplicate of their real-life home. It’s a collection of self-contained rooms without doors, moss crawling up the walls in corners, untamed houseplants covering side tables. One room resembles their living room, projector screen pulled down and home movie styled memories playing silently on it. Leo doesn’t glance too deeply into the other rooms; cast in shadows as they are, easily guessed to be unspoken off-limits. He’s more interested in the stacks and stacks of papers covering the atrium’s floor.

Comics, novels, loose printer paper, sketchbooks- some of them belong to their brothers, most of them belong to Mind Raph, his familiar large-font handwriting scrawled across covers and pages. Doodles and battle strategies coexist peaceably, interrupted in spots by to-do lists and memos. Leo snickers to himself at their contents- anything between ‘ham sandwiches for snack?’ to ‘ _that hard_ is too hard a punch, avoid spine snapping in the future’.

“So, you know the drill,” Leo says, smoothly twirling through the precarious piles, looking back towards Mind. “Lemme know about any weirdness happening ‘cause of the connection, some fun data points for Donnie to crunch on. Keep him busy with a nice new chew toy, yeah? Not jawbreaker level but definitely candied peanuts kinda tough. Yes I’m using a lot of chewing related metaphors, you know he _bit_ me last time we sparred, right? On the hand and everything! I swear, some people’s children.”

His ramble slows as he finds Mind, watching him with an odd look on his face. “What?” Leo asks, coming to a stop with his lazy circles.

“Not that hearing accounts of you two getting carried away with practice isn’t funny,” Mind says, crossing his arms, “but… I gotta ask, since we’re all feeling concerned about this.”

“About what?”

“Are you really okay? With leaving the link open?” Mind sighs and seems tired, somewhat wry. “Now that we’re all properly aware it’s _happening,_ it wouldn’t hurt my feelings if you wanted to close it. I know it… gets pretty messy in here, sometimes. We don’t want you to feel obligated to deal with it.”

“Dude,” Leo says with a huff, putting his hands on his hips. “I’m not doing any of this because I feel obligated. I’m doing this ‘cause it’s _really cool_ and a lot of fun and I love you, all of you. Long as we don’t have too many accidental bleed-overs anymore, then it’s good. Actually, it’s really convenient, too.” He grins widely. “Having a direct line to my big brother whenever I need it? Safe, speedy, and secure. The panic buttons got nothing on this arrangement.”

“You just like spamming me with badly remembered memes.”

“That too! But it’s mostly the nice stuff I said, I promise.”

Mind has a sad-happy look now and that’s not okay, so Leo- blinks- and pops over to the other side of the room, _thank you dream physics._ His pounce of a hug at his brother is caught and reciprocated without hesitation.

-/-

The incident with the Shredder shook all of them. It put _what-ifs_ in the back of Leo’s mind and makes him second guess himself. It left his siblings and their dad injured and exhausted. Its supernatural malevolence lingers all through New York months later.

They made it through all that, of course, but normalcy is something they have to work for every day after. Some things don’t go back to normal but that’s okay, too- or, it’s starting to be okay.

 _Baron Draxum_ is apparently a member of the family, now, which sure is… something. Maybe not a _bad_ something, but definitely a _weird_ something. Mikey calls him their other dad and Draxum has snippy conversations with Splinter at family dinners and honestly? At this point, it may as well happen. Their mad scientist yokai ‘parent’ is funny to watch struggle with modern appliances, at least.

Whatever. Leo sometimes has his brother’s voice(s) in his head, they could have had Big Mom as an _actual_ mom once upon a time, and the world nearly was destroyed a month and a half ago. Formally adding another member to their growing family tree is chump change by comparison.

So, the three days and nights of constant adrenaline and terror drift further and further from the present. The Shredder is long gone and won’t be missed. Leo and his family figure out how to correctly stitch Draxum into place. Their injuries heal over and their relationship starts to as well.

And Leo has one to two to three internal cheerleaders to help him navigate it all.

“Yo, Mind Raph?” Leo asks aloud, reaching for the now familiar tether inside himself and pulling on it to ring a metaphorical doorbell.

**Author's Note:**

> i don't care if the show runners ever outright deny/contradict my headcanons here. it's my quarantine and i get to pick the neurodiversity.
> 
> spare some comments/kudos for a starving writer? your nonlocal depressed/hyper anxious cryptid got flooded out of their basement room a week ago and was off their meds from then until today bc no time to refill them. some nice things to offset the murphy's law assault on my life would be appreciated (- ^ -;;;)


End file.
